there must be technology and investment in it, balanced by protection of the environment. then productivity can be safely increased to supply the demand of our people. for economics usa, i'm david schoumacher. captioning is made possible by the nenberg/cpb project captioning performed bytheg institute, inc. captions copyright 1986 educational film center annenberg media ♪ for information about this and other annenberg media programs call 1-800-learner and visit us at www.learner.org. annenberg media ♪ annenberg media ♪ it was 1927. once again, havoc reigne ♪ thughout the mississip and tennessee valleys. during a great depression, congress created the tva--